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More than a century after the idea was first floated, physicists have finally figured out how to tie water in knots in the laboratory. The gnarly feat, described today in Nature Physics1, paves the way for scientists to experimentally study twists and turns in a range of phenomena - ionized gases like that of the Sun's outer atmosphere, superconductive materials, liquid crystals and quantum fields that describe elementary particles.

Lord Kelvin proposed that atoms were knotted "vortex rings" - which are essentially like tornado bent into closed loops and knotted around themselves, as Daniel Lathrop and Barbara Brawn-Cinani write in an accompanying commentary. In Kelvin's vision, the fluid was the theoretical 'aether' then thought to pervade all of space. Each type of atom would be represented by a different knot.

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Kelvin's interpretation of the periodic table never went anywhere, but his ideas led to the blossoming of the mathematical theory of knots, part of the field of topology. Meanwhile, scientists also have come to realize that knots have a key role in a host of physical processes.

An alternative idea to the standard WIMP halo picture for the DM distribution in the galaxy

While humans have been writing for at least 5000 years, we have surprisingly little understanding of the physics underlying how ink moves from pen to paper. Now, physicists in South Korea and the US have worked out a theory - backed by experiment - that suggests the ink's flow rate depends on a tug-of-war that is played out between the capillary properties of pen and paper.

Researchers in Japan have developed what may be the first string-theory model with a natural mechanism for explaining why our universe would seem to exist in three spatial dimensions if it actually has six more. According to their model, only three of the nine dimensions started to grow at the beginning of the universe, accounting both for the universe's continuing expansion and for its apparently three-dimensional nature. ... The team has yet to prove that the Standard Model of particle physics will show up in its model,...

Seems as if the guy likes string theory ... Luzi won't be happy :-)

No comment!

Hall's team adopted an innovative approach to investigating Dirac's theory, creating and identifying synthetic magnetic monopoles in an artificial magnetic field generated by a Bose-Einstein condensate, an extremely cold atomic gas tens of billionths of a degree warmer than absolute zero.

interesting how the evolution theory is evolving maybe we could add this topic to the brainstorming session?

what an interesting personality ... very symathetic Peter Higgs, the British physicist who gave his name to the Higgs boson, believes no university would employ him in today's academic system because he would not be considered "productive" enough.

The emeritus professor at Edinburgh University, who says he has never sent an email, browsed the internet or even made a mobile phone call, published fewer than 10 papers after his groundbreaking work, which identified the mechanism by which subatomic material acquires mass, was published in 1964.

He doubts a similar breakthrough could be achieved in today's academic culture, because of the expectations on academics to collaborate and keep churning out papers. He said: "It's difficult to imagine how I would ever have enough peace and quiet in the present sort of climate to do what I did in 1964."

Speaking to the Guardian en route to Stockholm to receive the 2013 Nobel prize for science, Higgs, 84, said he would almost certainly have been sacked had he not been nominated for the Nobel in 1980.

Edinburgh University's authorities then took the view, he later learned, that he "might get a Nobel prize - and if he doesn't we can always get rid of him".

Higgs said he became "an embarrassment to the department when they did research assessment exercises". A message would go around the department saying: "Please give a list of your recent publications." Higgs said: "I would send back a statement: 'None.' "

By the time he retired in 1996, he was uncomfortable with the new academic culture. "After I retired it was quite a long time before I went back to my department. I thought I was well out of it. It wasn't my way of doing things any more. Today I wouldn't get an academic job. It's as simple as that. I don't think I would be regarded as productive enough."

Higgs revealed that his career had also been jeopardised by his disagreements in the 1960s and 7

And the follow up by Nobel prize winner Randy Schekman http://www.theguardian.com/science/2013/dec/09/nobel-winner-boycott-science-journals

interesting one - Luzi will like it :-)

Luca Turin presents a theory according to which the sense of smell is aroused by molecular vibrations instead of the shape-based compatibility with receivers on the proteins.

safe not only fossil fuels when biking but clean the air at the same time :-) (well... in theory)

If you've ever found your iPhone taking control of your life, there may be a good reason. It may think it has free will. That may not be quite as far-fetched as it sounds. Today, one leading scientist outlines a 'Turing Test' for free will and says that while simple devices such as thermostats cannot pass, more complex ones like iPhones might.

I don't know the inventor of that nonsense that the free will should be the result of QM. It's about the only point I agree with the author of the paper: QM is not necessary and doesn't help. What I meant: all these thought experiments done by typical ultra-naive realists (or ultra-naive physicalists, if you prefer) that cultivate the university departments of physics, computer science etc. are put the cart before the horse. First one has to clarify the role of physical theories and its concepts (e.g. causality) and then one can start to ask how "free will" could perhaps be seen in these theories. More than 200 years ago there existed a famous philosopher named Kant who had some interesting thoughts about this. But authors like Lloyd behave as if he never existed, in fact is view of the world is even pre-Platonic!

Henry Kissinger How I'm missing yer And wishing you were here

Ancient Earth might have had an extraterrestrial supply of vitamin B3 delivered by carbon-rich meteorites, according to a new analysis. The result supports a theory that the origin of life may have been assisted by a supply of key molecules created in space and brought to Earth by comet and meteor impacts.

Basically quantum entanglement, or more accurately the dispersal and expansion of mixed quantum states, results in an apparent flow of time. Quantum information leaks out and the result is the move from a pure state (hot coffee) to a mixed state (cooled down) in which equilibrium is reached. Theoretically it is possible to get back to a pure state (coffee spontaneously heating up) but this statistical unlikelihood gives the appereance of irreversibility and hence a flow o time. I think an interesting question is then: how much useful work can you extract from this system? (http://arxiv.org/abs/1302.2811) It should for macroscopic thermodynamic systems lead to the Carnot cycle, but on smaller scales it might be possible to formulate a more general expression. Anybody interested to look into it? Anna, Jo? :)

What you propose is called Maxwell's demon: http://en.wikipedia.org/wiki/Maxwell%27s_demon Unfortunately (or maybe fortunately) thermodynamics is VERY robust. I guess if you really only want to harness AND USE the energy in a microscopic system you might have some chance of beating Carnot. But any way of transferring harvested energy to a macroscopic system seems to be limited by it (AFAIK).

Time is an emergent phenomenon that is a side effect of quantum entanglement, say physicists. And they have the first exprimental results to prove it

I guess I tentatively agree with you on both points. In the end there might anyway be surprisingly little overlap between the way that we describe what nature does and HOW it does it... :-D

Congratulations! 100% agree.

Not again, pleeeaaase!!! Alright, you don't know the story, ask Dario or Leo...

he just did .... don't worry, it's already over again .... how are you btw?

... a theory of everytg. Dario, enjoy! :)

the guy is also a guru of brain imaging....... " and is currently the fourth most cited scientist in neuroscience and behavior in the world " - WoW

i think the guy was smoking something whilst writing this!!

the Alaskan bar-tailed godwit (Limosa lapponica baueri) (Figure 1), makes its eight-day, 11,000-km autumn migration from Alaska to New Zealand in one step, with no stopovers to rest or refuel. This roughly doubles the previous maximum direct flight distance in birds, challenging experts to square this remarkable marathon migration with our understanding of aerodynamic theory and endurance physiology.